In the second round, Silva threw a leg kick. Weidman checked the kick, and Silva immediately fell to the canvas – with his leg badly broken in one of the most gruesome injuries in mixed martial arts history.

Weidman threw an early front kick to the body, and 30 seconds in he shot for a single-leg takedown and landed it. He pushed Silva to the fence after the challenger returned to his feet, and there, he ate a knee. But as they clinched up and started to break, Weidman landed a punch that hurt the Brazilian.

Silva went to the canvas, and Weidman landed heavy hands up top as referee Herb Dean looked in closely. Silva survived the early storm but had to work off his back in guard as Weidman tried to work ground-and-pound. Several elbows landed for the champ with two minutes left, while Silva tried to return fire from his back as Weidman postured up.

Silva's shots from his back weren't ineffective, and frequently had Weidman turning his head away – and one of them cut the champ. Silva survived the round on his back to get to the second.

Silva kicked to the inside leg in the second, hoping to start the change of fortunes from the first. But in an absolutely stunning turn of events, a hard kick from Silva was checked by Weidman, and that was it.

The finish recalled memories of a bad leg break suffered by Corey Hill in a similar fashion in a 1997 fight. But that it happened to Silva, long considered the best pound-for-pound fighter in the world, as well as the greatest champion in UFC history, was shocking.

The end came 1:16 into the second round.

"No matter what happened in this fight, he's still the greatest of all time. I wish him the best, and God bless him," Weidman said. "That was the No. 1 thing I got hit with the first fight. I worked a lot with guys with kicks. But it's still crazy how that happened. There was a point I was just thinking, 'Ref, stop the fight.' His eyes were in the back of his head for a lot of those punches."

Weidman (11-0 MMA, 7-0 UFC) stayed unbeaten in the first defense of his title. Silva (33-6, 16-2) lost for the second straight time for the first time in his career – and at 38 years old, that may prove to be the end for "The Spider," as at best, a long recovery remains for him.